Once a draft is submitted formally under ASME procedures, the new Part will be published, and there will be opportunity for public comment

prior to ASME’s formal process, we need the first series of your comments and suggestions by 31 January, 2010. Comments must be exclusive to new construction of locomotive boilers, either riveted or welded (both types of construction will be treated in the new Part). Also our mandate does not include miniature boilers as defined in ASME Boiler Code, Section I, Part PMB. train@valornet.com, to be received not later than 31 January 2010. (Email is preferred)

_________________"It was not easy to convince Allnutt. All his shop training had given him a profound prejudice against inexact work, experimental work, hit-or-miss work."C. S. Forester

I'd suggest we start with a review of standards used in the UK, Europe and Asia where a few decades of relevant experience have been proven in practice over time and hundreds of thousands of ton-miles. No point reinventing the wheel.

dave

_________________Santayana: "He who does not remember the past is condemned to repeat it."Corollary: "He who does is doomed to watch those who don't repeat it anyway."

If you happen to know could you kindly explain to me how this process will take place?Robby

I’m on the outside as well, but the "National Board Inspection Code Committee (NBIC), Subgroup on Locomotive Boilers" is the "Engineering Standards Committee" of Part 230 fame, a.k.a The Gods of Steam. As I understand it, in their usual semi annual meetings they will start building the new locomotive boiler code using the parts of old and current codes that work with the needs of locomotive boilers, the FRA requirements, and today’s technology, and weeding out the parts of the current ASME Section I that are counterproductive with regard to locomotive boilers. That is where they need input from others with experience dealing with the ASME Code to be sure they cover all of the bases, and don’t miss anything.

filmteknik wrote:

Is there something they are seeking to change?

When steam locomotives were in widespread production, they had their own ASME boiler code. When they stopped being built, the locomotive code was dropped and ASME Section I for power boilers became the single rule for all new boilers. Over the course of time ASME Section I has evolved with new technology to the point that it is a poor fit for someone trying to design a locomotive boiler.For example, dome throttles, which most steam locomotives use, are not allowed. ASME Section I allows higher staybolt stresses and a lower factor of safety than the FRA requires, meaning that a new ASME locomotive boiler can be designed and built which the FRA will not allow to operate at its designed pressure. I’m sure other issues are in the current code, and it will make life easier for steam railroaders if they are corrected.

_________________"It was not easy to convince Allnutt. All his shop training had given him a profound prejudice against inexact work, experimental work, hit-or-miss work."C. S. Forester

I feel this is a very needed change. There has been so much confusion in this area and well intentioned but misinformed decisions made in new boiler design and all the way to the production floor. In the end case the brand new boiler is worthless to the locomotive and another boatload of money has been squandered. Over and over again well intentioned folks get caught up in either repairs or new builds by these ASME code shops that insist they know how to build a boiler. Of course they do know how, but you can't convince people that a locomotive boiler is not a power house boiler. Some BOD refuse to believe this too, then throw up there hands in frustration when the new design/repair won't meet FRA standards. Maybe the new rules won't help anyway, there seems to be an absolute refusal in some peoples agenda to accept the rules as they are now, so maybe new rules being more direct will not make any difference. But hopefully the manufacturer will be aided by knowing what the difference is and what it takes to meet the codes needed. Do not believe there are a lot of shops in the country that could design/build a new boiler to current FRA codes. Of course there are a few and a number of locomotives have new working boilers and a few coming on line soon with new boilers that are going to work, but there are a lot of disasters out there. By the time you make the "new" boiler compliant to FRA standards you could probably get it done cheaper by starting over. So much confusion still exists in repair and new construction. Then there are original bad or non compliant designs that were excepted but not right from day one. Copying an old design may not work either.

Anyway I am glad to see some attempt to address these issues. On the other hand if you don't understand or cannot except the FRA codes that already exist, the new clarification might not do any good. I highly recommend that if you have someone design a new boiler to replace your old one, have a knowledgeable professional check it out before you sign on the dotted line or start ordering materials. Talk to people that have gone at this before you. There are misguided folks who think a new boiler is going to be like swapping out a Cummings diesel with a new rebuild. Getting off topic sorry, maybe building new boilers should be a new thread? It is going to be more common and make more sense to go this route as time goes on. So again I am glad to see the clarification on the "books". Cheers, John.

When steam locomotives were in widespread production, they had their own ASME boiler code. When they stopped being built, the locomotive code was dropped and ASME Section I for power boilers became the single rule for all new boilers. Over the course of time ASME Section I has evolved with new technology to the point that it is a poor fit for someone trying to design a locomotive boiler.

Section III requirements were incorporated throughout Section I, not dropped all together. If two subjects conflicted (such as coefficients for allowable staybolt pitch) the more conservative value was invoked.

Kelly Anderson wrote:

For example, dome throttles, which most steam locomotives use, are not allowed.

I learn something new everytime I open the Code books. Could you please quote the dome throttle prohibition?

If you happen to know could you kindly explain to me how this process will take place?Robby

I’m on the outside as well, but the "National Board Inspection Code Committee (NBIC), Subgroup on Locomotive Boilers" is the "Engineering Standards Committee" of Part 230 fame, a.k.a The Gods of Steam. As I understand it, in their usual semi annual meetings they will start building the new locomotive boiler code using the parts of old and current codes that work with the needs of locomotive boilers, the FRA requirements, and today’s technology, and weeding out the parts of the current ASME Section I that are counterproductive with regard to locomotive boilers. That is where they need input from others with experience dealing with the ASME Code to be sure they cover all of the bases, and don’t miss anything.

filmteknik wrote:

Is there something they are seeking to change?

When steam locomotives were in widespread production, they had their own ASME boiler code. When they stopped being built, the locomotive code was dropped and ASME Section I for power boilers became the single rule for all new boilers. Over the course of time ASME Section I has evolved with new technology to the point that it is a poor fit for someone trying to design a locomotive boiler.For example, dome throttles, which most steam locomotives use, are not allowed. ASME Section I allows higher staybolt stresses and a lower factor of safety than the FRA requires, meaning that a new ASME locomotive boiler can be designed and built which the FRA will not allow to operate at its designed pressure. I’m sure other issues are in the current code, and it will make life easier for steam railroaders if they are corrected.

Older steamers may have picked their steam at the dome but for example even in the steam days they knew where the hot steam really is, NKP 765 has its steam pick just ahead of the cab in the boiler ahead of the firebox, that is where the hottest steam is. So a no dome throttle isn't surprising. For a new locomotive like the new Leviathan, a dome would be more for looks, but pick the steam ahead of the cab.

I learn something new everytime I open the Code books. Could you please quote the dome throttle prohibition?

Matt, I wouldn’t dream of being the code jockey that you are, even in my darkest nightmare, and have no interest or hope of competing with you on code questions. Also, I have no access to a copy of the code this week, but as I understand it, Section I has a requirement for a main steam stop valve immediately outside of the boiler shell, something that a dome throttle ain’t. If you have insights into ways around this problem and others in Section I, I’m sure the committee will be very interested in receiving your comments and assistance.

_________________"It was not easy to convince Allnutt. All his shop training had given him a profound prejudice against inexact work, experimental work, hit-or-miss work."C. S. Forester

I have never been able to specifically identify the prohibition on dome throttles, but an ASME interpretation ruled that they did not satisfy the requirements of the code.

This will be addressed in the new code, as will all (hopefully) other issues where confusion exists. To that end it is in the best interests of our industry to receive information from anyone who has any questions regarding the existing code.

So everyone understands, the new code will not stand alone but will be in support of PFT, PW, PR, PWT, and PG. It will hopefully be designed in such a manner that referenced section changes do not materially affect the intent of the locomotive requirements. It will still require users to be familiar with the entire section.

I believe we will be able to construct the locomotive part in a reasonably transparent manner however its completeness will depend upon the amount of meaningful information we have to work with. Hence the importance of hearing about any concerns regarding the existing document.

Well I do hope that fillet welded staybolts are included in the new code. While I am aware that this would potentially(long term) take money out of several peoples pockets (whom sit on the ESC) and does intimidate others, fillet welded bolts have several hundreds of millions of service miles through out europe and asia. Think maybe it's time we move up to late 30's european steam technology? I sure do, and I am well aware that I am not alone.

The FRA has already allowed "mudring" pins to be applied to a historic boiler on a tourist railroad, prior to the release of the new rules. So, fillet welded bolts should be a logical next step.

It is my opinion that fillet welds in this type of applications are dangerous and should not be used nor allowed at all. I strongly urge people to take a senior level Metallurgy corrosion coarse and failure analysis coarse before making a decision to allow fillet welded staybolts. The reduction in cross sectional areas should be enough to give any mechanical engineer grief. I understand that they are easier to weld and can create a lot of work for a contractor maintaining a locomotive but in the greater interest in safety they should not be allowed.

Robby Peartree

M Austin

Post subject: Dome Throttles

Posted: Mon Jan 04, 2010 2:31 am

Joined: Sat Feb 05, 2005 1:05 amPosts: 416

Linn,

My Code books are spread over 5000 miles currently. Would you be so kind as to post the Interpretation relevant to dome throttles?

Thanks,

Matt Austin

M Austin

Post subject: Fillet Welded Staybolts

Posted: Mon Jan 04, 2010 3:37 am

Joined: Sat Feb 05, 2005 1:05 amPosts: 416

During the last five years or so, I have attended 3 or 4 ESC meetings. Everytime the fillet welded staybolt issue came up for discussion, I suggested to the Fillet Welded Faction (which I don't believe includes a single graduate engineer) that the following steps be taken:

1. Locate the mechanical engineering department of any university.2. Find any professor and suggest this senior project be assigned.3. Create a finite element analysis of stress values for 3 different variations of staybolt attachment:A. 12 thread per inch - USFB. full penetration weldC. fillet weld

The variables should be 4" X 4" staybolt pitch, 3/8" sheet thickness and 200 psi working pressure. Stress and deformation are a function of geometry, material is irrelevant for this analysis.

To my knowledge, this analysis, nor any derivative thereof, has yet been accomplished.

To argue before the Main Committee of the American Society of Mechanical Engineers that "The Germans did it in the 1950's" and "A billion Chinese did it and didn't kill anybody we know of...." is..... is....... well....

I suggest you first sharpen your pursuasion tools by trying to convince the American Medical Association to endorse Chinese herbal cancer cures before you use this logic to try to pull off selling the ASME on fillet weld staybolts without fundamental engineering analysis.

These days you might as well do a thermal expansion fatigue analysis right out of the gate. It will have to be done before this gets approved anyway.

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